Vacuum treatment apparatus

ABSTRACT

To reduce pumping time of a vacuum treatment chamber served by a transport arrangement in a transport chamber. The vacuum treatment chamber is split in a workpiece treatment compartment and in a pumping compartment in mutual free flow communication and arranged opposite each other with respect to a movement path of the transport arrangement serving the vacuum treatment chamber. The pumping compartment allows providing a pumping port of a flow cross-section area freely selectable independently from the geometry of the treatment compartment.

The present invention is generically directed on a vacuum treatmentapparatus, whereat one or more than one vacuum treatment chambers areprovided, which is or which are served with workpieces to be treated bya transport arrangement within a vacuum transport chamber, which lattercommunicates with one or more than one treatment chambers by openings,through which the workpiece is fed into or removed from the treatment.Thereby, there is specifically addressed such apparatus, at which thevacuum treatment chamber must be sealed off from the transport chamberduring treatment of the one or more than one workpieces and is to bepumped down on a vacuum level necessary for the respective vacuumtreatment after having been sealed off from the transport chamber. Suchapparatus are e.g. known from the U.S. Pat. No. 6,481,955 or the WO2010/105967.

It is an object of the present invention to provide such apparatus withimproved pumping down times of the vacuum treatment chamber or chambers.

We understand under a “vacuum treatment” any vacuum processing of aworkpiece, so e.g. any PVD or CVD vacuum process or other vacuumprocesses in which the workpieces are surface treated under pressuresbelow atmospheric pressure i.e. under vacuum conditions.

The addressed object is resolved according to the present invention by avacuum treatment apparatus which comprises a vacuum treatment chamberand a vacuum transport chamber. The vacuum transport chamber comprises atransport arrangement with at least one workpiece support and isdrivingly movable along a movement path. The transport chambercommunicates via an opening with the treatment chamber and is conceivedto pass therethrough at least a part of the transport arrangement, theworkpiece support and a workpiece therein along the movement path. Thevacuum treatment chamber comprises a workpiece treatment compartment onone side of the movement path and a pumping compartment opposite theaddressed workpiece treatment compartment with respect to the movementpath. The pumping compartment comprises a pumping port. There is furtherprovided a controllable sealing arrangement which controllably seals offthe addressed opening between the transport chamber and the overallvacuum treatment chamber.

Thus, the overall vacuum treatment chamber is divided in a workpiecetreatment compartment and in a pumping compartment which are providedopposite each other on both sides of the moving path of the transportarrangement and which are in complete flow communication. It is therebyachieved that there is in fact no limit for conceiving the extent of thepumping port as not provided in the workpiece treatment compartment.This allows installing high-capacity pumping, which is significantlydetermined by the flow cross-section of pumping line on the low pressureside of a pumping arrangement.

As the addressed separation of the overall vacuum treatment chamber in aworkpiece treatment compartment and in a pumping compartment allowsinstalling high pumping capacity, the possibility is opened to at leastsubstantially evacuate also the transport chamber by a vacuum pumparrangement connected to the addressed pumping port at the pumpingcompartment.

By means of the controllable sealing arrangement—once the workpiece isloaded in the treatment chamber and thus ready to be treated byprocessing action of the treatment compartment, the transport chamber issealed from the vacuum treatment chamber. The pumping arrangementconnected to the addressed pumping port in the pumping compartment canrapidly evacuate the overall treatment chamber including the treatmentcompartment to that vacuum level necessitated for the intended vacuumprocess.

Especially in apparatus which make use of the present invention and areconceived with multiple vacuum treatment chambers served by a commontransport arrangement it is highly advantageous to provide thepossibility to open selected ones of the vacuum treatment chambers toambient e.g. for maintenance purposes. Such flooding of a part of theoverall apparatus to ambient should not affect the remaining vacuumareas of the apparatus. This e.g. to exchange workpieces under ambientpressure, to minimize standstill times of the overall apparatus, or evento allow further workpiece processing by the apparatus in spite of theone treatment chamber being flooded to ambient.

Under this aspect in one embodiment of the present invention thecontrollable sealing arrangement is conceived so as to increase sealingforce as the pressure in the treatment compartment and in an area of thepumping compartment in flow communication with the pumping portincreases. In other words whenever according to the present inventionthe transport chamber is sealed off from the treatment compartment andpressure in the pumping compartment or at least that area in the pumpingcompartment which is in flow communication with the pumping port and inthe workpiece treatment compartment rises e.g. to ambient pressure, thenthe seal effect of the sealing arrangement is increased. As known to theskilled artisan, such conception may generically be fulfilled byrespectively tailoring the extent of surface areas which are loaded witha respective pressure in seal-closing direction. The embodiment as justaddressed may be combined with any of the subsequently addressedembodiments.

In spite of the fact that under a generic aspect the apparatus accordingto the present invention may be conceived so that the sealingarrangement may only establish sealing separation between the transportchamber and the treatment compartment/pumping compartment once thetransport arrangement has been removed from the vacuum treatmentchamber, thereby leaving the workpiece in the vacuum treatment chamber,in one embodiment of the present invention, which may be combined withany of the embodiments already addressed or addressed in the followingunless in contradiction, the controllable seal arrangement is conceivedto seal off the addressed opening as the transport arrangement is in aposition at which the workpiece support on the transport arrangementresides within the vacuum treatment chamber. In this embodiment thetransport arrangement remains within the vacuum treatment chamber duringtreatment of the workpiece.

In one embodiment of the present invention which may be combined withany embodiment already addressed or subsequently addressed unless incontradiction, the controllable sealing arrangement comprises adrivingly extendable and retractable tubular bellow. One end of thetubular bellow is sealingly mounted in the pumping compartment. Theother end of the tubular bellow is controllably movable about theopening to seal off the opening. The pumping port is located in an areaof the pumping compartment which is in flow communication with theinside of the bellow. By providing such tubular bellow it becomespossible, curtain-like, to move the movable end of the bellow sealinglyacross the addressed opening. Then the treatment compartment is in freeflow communication through the inside of the bellow with the pumpingport in the pumping compartment.

In one embodiment of the present invention making use of the addressedtubular bellow, the transport chamber extends across the vacuumtreatment chamber. It thus communicates also with a second opening whichis conceived to pass the transport arrangement, the workpiece supportthereon and the workpiece disposed therein. The second opening islocated opposite the one opening in the wall of the vacuum treatmentchamber. The other end, i.e. the free end of the bellow, is sealinglymovable also about the second opening. Thus, by respectively controllingthe movement of the free end of the tubular bellow, both communicationopenings of the transport chamber to the vacuum treatment chamber maysimultaneously be sealingly closed.

In one embodiment of the embodiment just addressed the transportarrangement is movable along the movement path and along the vacuumtreatment chamber, through the addressed first and second openings andcomprises a multitude of spaced-apart workpiece supports. In thisembodiment inline treatment of a multitude of workpieces is performed inthe addressed one vacuum treatment chamber.

In one embodiment of the present invention which may be combined withany embodiment as already addressed and as subsequently addressed unlessin contradiction, the workpiece support on the transport arrangementcomprises a through-opening. A workpiece support member is held in thethrough-opening and is liftable in direction towards the treatmentcompartment, thereby leaving its seat on the transport arrangement. Theother end, i.e. the free end, of the tubular bellow is drivingly movablein a sealing contact with the addressed workpiece support member so asto lift this member into a sealing contact with an annular area along awall of the treatment compartment. Thus, by driven movement of the freeend of the tubular bellow the workpiece support member is lifted fromthe through-opening of the transport arrangement and is pressedsealingly towards the addressed annular area along the inner wall of thetreatment compartment. Thereby, the free end of the tubular bellow aswell is sealingly biased on the workpiece support member.

In one embodiment of the present invention and departing from theembodiment just addressed, the apparatus comprises a lift arrangementwhich is controllably liftable from the pumping compartment towards andinto the treatment compartment. The lift arrangement is located insidethe tubular bellow. It comprises an actuator to liftably cooperate withthe open end of the tubular bellow so as to lift it into the addressedsealing contact with the workpiece support member and to lift theworkpiece support member further in sealing contact with the annulararea along the wall of the treatment compartment. Thus, by lifting thelift arrangement towards the treatment compartment the actuator at thelift arrangement lifts the open end of the tubular bellow up tocontacting the workpiece support member, lifting latter towards and ontothe annular area along the wall of the treatment compartment andestablishing there a seal on one hand between the addressed annular areaand the workpiece support member, and on the other hand between theworkpiece support member and the upper end of the tubular bellow.

In one embodiment of the invention the addressed workpiece supportmember comprises a support plate with through-openings along itsperiphery. In this embodiment the workpiece to be treated is and stayslocated upon the support member and will be positioned according to thatposition the support member assumes when establishing the seal with theannular area along the wall of the treatment compartment. The treatmentposition of the workpiece and the sealing position of the workpiecesupport plate are not independent. The support plate hasthrough-openings along its periphery—the workpiece resides in the centerof the support plate—to establish free flow communication between thetreatment compartment and the pumping port in the pumping compartment.

In a further embodiment of the invention the workpiece support membercomprises a frame which may e.g. be circular or rectangular, genericallyadapted on the outer frame circumference to the shape of thethrough-opening in the transport arrangement and on the inner framecircumference to the shape of one or of a multiple of workpieces to betreated. The frame comprises holding members for the at least oneworkpiece within its inner open area. The holding members are conceivedto allow lifting off the one or more than one workpieces from the framein direction towards the treatment compartment. The actuator on the liftcooperates via a spring arrangement with the other end (the free end) ofthe tubular bellow. The lift arrangement comprises a workpiece supportplate located at the end of the lift arrangement towards the treatmentcompartment. By this embodiment all the addressed seals of the workpiecesupport member, namely of the frame towards the annular area along thewall of the treatment compartment and between the open end of thetubular bellow and the addressed frame, are established but additionallyand due to the spring arrangement acting between the actuator and thefree end of the tubular bellow the lift arrangement may lift theworkpiece on the support plate from the frame and position the workpiecewithin the treatment compartment at a position which is independent fromestablishing the addressed seals.

In one embodiment of the apparatus according to the invention, which maybe combined with any of the embodiments already addressed or to beaddressed unless in contradiction an additional mechanism is included tolift the workpiece from the workpiece support plate so that the positionof the workpiece becomes independent from the position of the workpiecesupport plate. If, as an example, the workpiece support plate isequipped with heating or cooling facilities for the workpiece, then theaddressed additional mechanism may be exploited to adjust heattransition to or from the workpiece even during treatment of theworkpiece. Thereby an adjusting member is realized for controllingtemperature of the workpiece, e.g. in a negative feedback control loop.

This embodiment thus comprises a workpiece treatment holder for saidworkpiece in the workpiece treatment chamber and a controllably drivablelifting arrangement for a workpiece on said workpiece treatment holder.

In a variant of this embodiment a temperature sensing means adapted tosense a temperature of the workpiece on said workpiece treatment holderis provided, whereby the temperature sensing means and the controllablydrivable lifting arrangements are operatively connected in a negativefeedback loop for the temperature of the workpiece.

In one embodiment of the apparatus according to the invention, which maybe combined with any of the embodiments already addressed or to beaddressed unless in contradiction and whereat the transport arrangementis movable along its movement path through the vacuum treatment chamberthe transport arrangement is movable along a linear or along a circularmoving path. The overall apparatus according to the present inventionmay be an apparatus, where multiple workpieces are conveyed by a lineartransport arrangement in an indexed manner from one vacuum treatmentfacility to the next, at least one thereof being conceived according tothe present invention, or the overall apparatus may be conceived with atransport arrangement which is driven about a center in a circularmanner and multiple workpieces are thereby conveyed from one vacuumtreatment facility to the next again in an indexed manner.

In one embodiment, which may be combined with any of the embodimentsalready addressed or to be addressed unless in contradiction and whereatthe transport arrangement is movable along a circular moving path, thetreatment compartment and the pumping compartment are arranged oppositeeach other in direction of an axis of the circular moving path.

In one embodiment of the present invention, which may be combined withany of the addressed embodiments, the apparatus further comprises afirst pumping arrangement which is operationally connected to thetransport chamber and which is conceived to evacuate the transportchamber. It further comprises a second pumping arrangement which isoperationally connected to the treatment compartment and which isconceived to evacuate the treatment compartment. Thereby, a pumpingarrangement is connected to the pumping port of the pumping compartmentand it is this pumping arrangement which is at least a predominant partof the pumping arrangement conceived to evacuate the transport chamberand which is exclusively the pumping arrangement which is conceived toevacuate the treatment compartment.

The present invention shall now be further exemplified with the help offigures. They show:

FIG. 1 schematically and simplified, a first embodiment of the apparatusaccording to the present invention, whereat a transport arrangement isremoved from the vacuum treatment chamber during treating a workpiece;

FIG. 2 in a representation in analogy to that of FIG. 1, a secondembodiment of the invention, whereat the transport arrangement remainsin the vacuum treatment chamber during vacuum treatment of theworkpiece;

FIG. 3 still in a schematic representation, a further embodiment of theinvention in analogy to that of FIG. 1;

FIG. 4 a part of an embodiment of the apparatus according to theinvention and according to FIG. 3, whereat high-pressure in a treatmentcompartment as provided by the apparatus according to the inventionstrengthens a seal;

FIG. 5 in a more detailed, still schematic representation, a furtherembodiment of the apparatus according to the invention, combiningfacilities of the embodiment of FIGS. 2 and 3;

FIG. 6 in a representation in analogy to that of FIG. 5, a further todayrealized embodiment of the present invention;

FIG. 7 most schematically, a part of an apparatus according to theinvention with a linear transport arrangement;

FIG. 8 in a representation according to that of FIG. 7, the apparatusaccording to the invention with a circular centrally driven transportarrangement, and

FIG. 9 still in a representation in analogy to those of FIGS. 7 and 8,an apparatus according to the invention with a ring-shaped circulartransport arrangement.

By means of FIGS. 1 and 2 the generic concept according to the presentinvention shall be described. Within a transport chamber 1 which isevacuatable as e.g. with a transport chamber pump arrangement 3 atransport arrangement 5 is controllably drivable along a moving pathshown in dash line, S. The transport arrangement 5 has at least oneworkpiece support 7 for a workpiece 9 to be treated. The transportchamber 1 communicates via an opening 11 with a vacuum treatment chamber13. The vacuum treatment chamber 13 comprises on one hand a workpiecetreatment compartment 13 _(T) on one side of the movement path S of thetransport arrangement 5 and, opposite to the treatment compartment 13_(T) with respect to the movement path S, a pumping compartment 13 _(P).According to FIG. 1 there is provided along the movement path S of thetransport arrangement 5 in the vacuum treatment chamber 13 a workpiecereceiving member 15 upon which the workpiece 9 is deposited by thetransport arrangement 5 as shown in dash line. After deposition of theworkpiece 9 in the vacuum treatment chamber 13 and according to theembodiment of FIG. 1 the transport arrangement 5 is retracted e.g. in aposition as shown in FIG. 1 out of vacuum treatment chamber 13.

After deposition of the workpiece 9 on support 15 a sealing arrangement17, which as schematically shown in FIG. 1 is controllably driven as bya drive 20, to move across opening 11 and to seal off opening 11. Thesealing arrangement 17 in sealing position is shown in dash line.

Thereby, the vacuum treatment chamber 13 including both mutually freelycommunicating compartments 13 _(T) and 13 _(P) are sealingly separatedfrom transport chamber 1. The workpiece on support 15 is exposed to avacuum treatment in treatment compartment 13 _(T). Accordingly (notshown in FIG. 1) the treatment compartment 13 _(T) is equipped withunits to perform a desired workpiece treatment e.g. with sputteringsources, arc evaporators, gas supplies, plasma discharge units as forPECVD treatment, heaters, coolers, etc.

In the pumping compartment 13 _(P) there is provided a large pumpingport 18 to apply a pumping arrangement 19. The pumping compartment 13_(P) provides for a large surface area allowing to apply such largepumping port 18 with very large cross-section for the pumpingarrangement 19 so that the overall vacuum treatment chamber 13 includingthe treatment compartment 13 _(T) may rapidly be pumped down to vacuumpressure as desired. Thereby, the pumping effect of pumping arrangement19 may be tailored so large that whenever the opening 11 is free fromsealing arrangement 17 this pumping arrangement 19 may also be exploitedto provide at least predominant pumping effect upon the transportchamber 1. In such case the transport chamber pumping arrangement 3becomes only an auxiliary arrangement, if at all necessary. If thetransport arrangement serves more than one of the vacuum treatmentchambers 13, the respective pumping arrangements 19 commonly also act astransport chamber pumping arrangement.

Reference No. 22 schematically shows the controllable drive for thetransport arrangement 5.

Whereas in FIG. 1 an embodiment is schematically shown in which thetransport arrangement 5 is retracted from the vacuum treatment chamber13 before treatment is performed therein and thus before the sealingarrangement 17 sealingly closes opening 11, FIG. 2 shown in an analogousrepresentation an embodiment in which the transport arrangement 5remains with the workpiece 9 resting thereon within the vacuum treatmentchamber 13 during workpiece treatment.

According to the embodiment of FIG. 2 the sealing arrangement 17 _(a) isconceived between the transport arrangement 5 and the border of opening11 so that the opening 11 is shut off whenever the transport arrangement5 is completely introduced into the vacuum treatment chamber 13 andremains there for the treatment of workpiece 9.

Departing from the general approach of the present invention accordingto FIG. 1, FIG. 3 shows in a representation in analogy to that of theFIGS. 1 and 2 one embodiment to realize the apparatus of FIG. 1. In thepumping compartment 13 _(P) there is sealingly mounted a tubular bellow21. The tubular bellow 21 is drivingly and controllably extractabletowards the treatment compartment 13 _(T) and accordingly retractableinto the pumping compartment 13 _(P). The pumping port 18 for pumpingarrangement 19 is provided in the wall of the pumping compartment 13_(P) inside the tubular bellow 21. Thus in fact, inside pumpingcompartment 13 _(P) a pumping area 13 _(P)′ is established inside bellow21. The open end of bellow 21 towards the treatment compartment 13 _(T)is controllably driven, as schematically shown by drive 20, movable in aposition sealingly closing off opening 11 with respect to the pumpingarea 13 _(P)′ and the treatment compartment 13 _(T), which both are keptin open communication when the opening is sealingly closed. According toFIG. 3 this is realized by providing at that end of bellow 21 pointingtowards the treatment compartment 13 _(T) a sealing ring or frame 25which sealingly engages a shoulder surface 27 of the vacuum treatmentchamber 13. With respect to opening 11 and movement path S the ring- orframe-shaped shoulder surface 27 is located towards the treatmentcompartment 13 _(T).

It is often necessary e.g. for workpiece exchange, for maintenancepurposes or, for exchanging a treatment facility to open the treatmentcompartment 13 _(T) and thereby to expose the overall vacuum treatmentchamber 13 to ambient pressure. Thereby, it should be prevented on onehand that the remaining of the treatment apparatus with the transportchamber 1 and possibly additional treatment facilities served by thetransport arrangement 5 become contaminated or will have to bere-evacuated. Often it might also be desired to continue workpiecetreatment by the apparatus although one of the multiple treatmentfacilities being under maintenance, more generically being open toambient pressure. Therefore, in one embodiment as exemplifiedschematically in FIG. 4, as an example for the embodiment of FIG. 3, thesealing arrangement is conceived so that a pressure difference existingbetween the vacuum treatment chamber 13 at a higher pressure and thetransport chamber 1 at lower pressure relative to the pressure in thetreatment chamber, provides for an increased sealing force upon sealingof the opening 11.

This is generically realized by providing surfaces at the movablesealing arrangement which are exposed to the pressure difference frompressure in treatment compartment 13 _(T) and pumping compartment 13_(P) and pressure in the transport chamber 1, so that the resultingforce points towards the sealing engagement. Departing from theembodiment of FIG. 3 FIG. 4 shows such an embodiment. After havingestablished the seal with respect to ring or frame shoulder surface 27the surface of sealing ring 25 in the bellow 21 is exposed along surfacearea F shown crosshatched in FIG. 4 to the pressure p_(a) in thetreatment compartment 13 _(T) and pumping area 13 _(P)′ while theopposite surface of sealing ring 25 is exposed to the lower pressure Pvof the transport chamber 1. Creating such a pressure difference along asurface area as of F and over sealing ring 25 leads to a resulting forceQ as shown in FIG. 4 on the sealing ring 25 which points in seal-closingdirection. This is realized in that with respect to the axis A of thetubular bellow 21, the seal 7′ at sealing ring 25 to shoulder 27 in FIG.4 is established along a ring area with a radius R_(7′), which issmaller than the radius R₂₁ to the ring area whereat the sealing ring 25is sealingly linked to the end of tubular bellow 21.

In the embodiment as schematically shown in FIG. 5 the approachesaccording to FIG. 2 and of FIG. 3 are combined, i.e. FIG. 5 shows anembodiment wherein the transport arrangement 5 remains in the vacuumtreatment chamber 13 when the workpiece 9 is treated by action from thetreatment compartment 13 _(T) and the opening 11 to the transportchamber 1 is sealingly closed making use of a tubular bellow 21.

The transport arrangement 5′ has a through-opening 31. Thethrough-opening 31 is e.g. circular.

The border of the through-opening 31 defines for a support shoulder 33or more generally a retaining arrangement. A workpiece carrier plate 35rests within through-opening 31 upon support shoulder 33.

Thus, workpiece carrier plate 35 may be freely lifted from the transportarrangement 5′ towards the treatment compartment 13 _(T). The positionof the workpiece carrier plate 35 as resting in the through-opening 31of transport arrangement 5′ is shown in dash line.

The upper end of tubular bellow 21 is sealingly joint to sealing ring25. The drive 20 as schematically shown in FIG. 3 to lift and retractbellow 21 is realized in the embodiment according to FIG. 5 by a liftingarrangement 20′ controllably driven (not shown in FIG. 5). A lifting rod37 coaxially to the axis A of the tubular bellow 21 is guided in avacuum-tight lead-through 39 through the wall of the pumping compartment13 _(P) and carries at its end pointing towards the treatmentcompartment 13 _(T) a lifting plate 41.

The lifting plate 41 is tailored so as to engage the sealing ring orframe 25 at the end of bellow 21, thereby lifting sealing ring 25 insealing engagement with workpiece carrier plate 35 and thereby liftingthis plate 35 in sealing engagement with shoulder ring surface 27. Thelifting plate 41 has a multitude of or a few large through-openings 43along its periphery. The workpiece carrier plate 35 as well has amultitude of or a few large through-openings 45 along its periphery. Theworkpiece support 7 for workpiece 9 is provided primarily by the surfacetowards treatment compartment 13 _(T) in the central area of theworkpiece carrier plate 35.

FIG. 6 shows in a representation analogous to that of FIG. 5 a furtherembodiment of the present invention which is realized today. The genericdifferences with respect to the embodiment of FIG. 5 are that theembodiment according to FIG. 6 comprises a transport arrangement and arespectively construed transport chamber which passes through the vacuumtreatment chamber and is thus perfectly suited to be realized in theframe of a vacuum treatment apparatus, whereat substrates aretransported from one vacuum treatment facility to the other in aone-directional indexed manner. Additionally, the embodiment accordingto FIG. 6 allows positioning the workpiece within the treatmentcompartment independently of establishing a seal between the treatmentcompartment/pumping compartment on one hand and the transport chamber onthe other hand.

FIG. 6 shows the apparatus in workpiece treatment position.

According to the embodiment of FIG. 6 a transport chamber 61communicates by two opposed openings 71 with the vacuum treatmentchamber 73. A transport arrangement 65, which is shaped as a circulardisk plate, a ring plate or a linear extending band-shaped plate,resides in transport chamber 61 and runs through the vacuum treatmentchamber 73. The transport arrangement 65 is controllably drivingly movedby a respective drive (not shown in FIG. 6) either in one direction orforth and back in an indexed manner and then transports in each indexcycle a workpiece support area 66 centralized into vacuum treatmentchamber 73. The vacuum treatment chamber 73 comprises on one side ofmovement path S of the transport arrangement 65 a treatment compartment75 _(T) and with respect to the addressed movement path S opposite tothe treatment compartment 75 _(T) a pumping compartment 75 _(P). Thetransport arrangement 65 comprises in the workpiece support area 66, inanalogy to the embodiment of FIG. 5, a through-opening 77 wherein asealing ring 79 resides similarly to workpiece carrier plate 35 in therespective through-opening in transport arrangement 5′ of FIG. 5. Thesealing ring 79 comprises support members 81 which radially project intothe ring 79. Further, in analogy to the embodiment of FIG. 5, there isprovided a tubular bellow 83. One end of the tubular bellow 83 issealingly linked to a ring shoulder surface 85 of the pumpingcompartment 75 _(P). The opposed end of tubular bellow is sealinglylinked to a second sealing ring 87. A lifting arrangement providedcoaxially to the tubular bellow 83 about axis A comprises a lifting rod89 which passes by a vacuum-tight lead-through 91 through the wall ofpumping compartment 75 _(P) and is controllably movable up and down bydrive 93.

Lifting rod 89 is provided with a flange 95 as an actuator. Flange 95 isrigidly mounted to lifting rod 89. The flange supports towards thetreatment compartment 75 _(T) an arrangement of springs 97, whichsupports a lifting plate 99 which is movable along the lifting rod 89and resides and is supported on and by the spring arrangement 97 withrespect to flange 95.

There is further provided a large pumping port 101 communicating withthe interior of the tubular bellow 83 which thus in analogy to theembodiment of FIG. 5 forms a pumping area 75 _(P)′.

The lifting plate 99 comprises wide through-openings 105. The end of thelifting rod 89 towards the treatment compartment 75 _(T) is equippedwith a workpiece-lifting plate 103 which may be provided with e.g. apassive chuck or an active chuck as with an electrostatic chuck forholding workpiece 107, e.g. a disk-shaped workpiece as e.g. a wafer.

Alternatively or additionally, the workpiece 107 may be held uponlifting plate 103 as commonly known in the art by a weight-ring (notshown) residing on the periphery of workpiece 107.

The embodiment according to FIG. 6 operates as follows:

When the lifting plate 103 is completely retracted towards the pumpingcompartment 75 _(P) the transport arrangement 65 is freely movablethrough the vacuum treatment chamber 73. The pumping arrangement (notshown in FIG. 6) connected to large pumping port 101 pumps vacuumtreatment chamber 73 as well as transport chamber 61. The transportarrangement 65 is then moved e.g. as shown by the arrow I in an indexedmanner so as to locate the workpiece support area 66 centralized intothe vacuum treatment chamber 73. The workpiece 107, as e.g. a wafer,resides in sealing ring 79, held by support members 81, and sealing ring79 resides in through-opening 77 supported along the border ofthrough-opening 77 on the transport arrangement 65. Lifting plate 103being completely retracted below the movement path S of the transportarrangement 65 and thus below transport arrangement 65, the tubularbellow 83 with second sealing ring 87, flange 95 with spring arrangement97, supported lifting plate 99 are all retracted below the transportarrangement 65. The high-capacity vacuum pump connected to pumping port101 e.g. continuously running, the lifting rod 89 is lifted by drive 93.By the lifting movement of flange 95 and yet substantially unbiasedspring arrangement 97 the lifting plate 99 is lifted and engages secondsealing ring 87 sealingly joint to the upper end of tubular bellow 83.The lifting plate 103 lifts workpiece 107 out of its support by supportmembers 81 at sealing ring 79. The second sealing ring 87 is lifted bythe lifting plate 99 towards sealing ring 79′, thereby the sealing ring79 is lifted upwards up to sealingly resting against ring-shapedshoulder surface 109 at the treatment compartment 75 _(T). Thereby thesecond sealing ring 87 sealingly engages the sealing ring 79 and theseal between ring shoulder surface 109, sealing ring 79 and secondsealing ring 87 is established by the biasing force of lifting plate 99against the force of spring arrangement 97. In spite of the fact thatthe sealing ring 79 with support member 81 for the workpiece 107 alreadysealingly resides against ring shoulder 109, the lifting rod 89 isfurther driven upwards against the biasing force of spring arrangement97 and lifts the workpiece 107 in that position within treatmentcompartment 75 _(T) where it will be treated by the installed vacuumprocess. This position is shown in FIG. 6. Summarizing, whenever theworkpiece 107 with lifting plate 103 has been moved in treatmentposition, there is established a seal between second sealing ring 87 andsealing ring 79, between sealing ring 79 and ring shoulder surface 109.The tubular bellow 83 separates the pumping area 75′_(P) from that areaof the vacuum treatment chamber 73 wherein the transport chamber 61communicates via openings 71. Free flow communication between thetreatment compartment 75 _(T) and pumping port 101 is established viawide open through-opening of sealing ring 79, wide open second sealingring 87, large through-openings 105 in lifting plate 99 and large innerspace left open by ring shoulder surface 85.

Once the workpiece 107 has been treated as desired, the lifting rod 89is retracted whereby the addressed seals are opened and workpiece 107together with sealing ring 79 are placed back upon the transportarrangement 65, which then may be further indexed as all the membersoperationally coupled to the lifting rod 89 are retracted back into thepumping compartment 75 _(T) and thus do not encumber movement of thetransport arrangement 65.

Due to the fact that, according to the present invention, there isprovided a separate compartment aside of a treatment compartment,wherein a workpiece is vacuum treated, and further in flow communicationwith the addressed treatment compartment and a switched flowcommunication from the treatment compartment to a transport chamber witha transport arrangement for delivering at least one workpiece into andremoving such at least one workpiece once treated, there is ample spaceavailable for providing a pumping port of very large cross-section alsofor the treatment compartment. Thereby very fast pumping down of thetreatment compartment onto a desired low vacuum becomes possible.

With an eye on FIG. 4 it has to be noted that also in the embodiments ofFIG. 5 or 6 it is advantageously realized that whenever the treatmentcompartment is opened to ambient, e.g. for maintenance purposes, theambient pressure increases the sealing forces on the seals separatingthe treatment compartment from the transport chamber. Still with an eyeon FIG. 4 the surface considerations which have been explained incontext with that fig. are also valid for the embodiment of FIG. 5 or 6e.g. with respect to second sealing ring 87 and bellow 83 in analogy torealization of sealing ring 25 and bellow 21 of FIG. 4.

As was already addressed, the apparatus according to the presentinvention, as of FIG. 6, is perfectly suited for an indexed transport ofa multitude of workpieces along several vacuum treatment stations atwhich the workpieces have consecutively to be treated.

As exemplified in context with FIG. 6 lifting pins 109 synchronouslyliftable and retractable by respective drives 111 with respect to thesurface of the lifting plate 103 whereupon the workpiece 107 resides.Thereby the workpiece may be controllably and accurately lifted from theaddressed surface also during treatment of the workpieces.

If e.g. the lifting plate 103 is equipped with a heating and/or coolingfacility 115, the exchange of heat between the lifting plate and theworkpiece may be adjusted by controlled adjustment of the distancebetween the workpiece bottom surface and the lifting plate top surface.

By providing a temperature sensing device 117 for the workpiecetemperature, the output of which being compared with a rated, desiredtemperature value at a comparator unit 119, the output of which,according to the comparison result, acting on the drives 111 a negativefeedback control is for the workpiece temperature is established,exploiting the lifting pin arrangement as an adjusting member. Clearlysuch pin arrangement and possibly such control loop may be provided inany embodiment of the invention where the workpiece resides on a supportduring treatment.

FIG. 7 most schematically shows such an apparatus according to theinvention, where at least one of a multitude of vacuum treatmentchambers is realized according to the present invention and all vacuumtreatment chambers are served by a common transport arrangement in alinearly indexed manner as shown by the arrows W. If all vacuumprocesses to be performed by such vacuum treatment stations 10 a . . .110 c necessitate separate pumping on respective processing vacua, thenall such stations are realized as has been exemplified by theembodiments as especially of FIG. 6. If on the other hand one or theother process does not need separate pumping, then the respective vacuumtreatment chamber may be realized conventionally without pumping port.Whereas according to FIG. 7 the transport arrangement schematicallyshown in dash line at 112 is indexed in a linear movement, FIG. 8 showsin an analogous representation an overall apparatus, wherein indexedtransport is realized by a circular plate-type transport arrangement112′. In a similar representation FIG. 9 shows still another embodimentof an overall apparatus according to the present invention, whereinindexed workpiece transport is realized by means of a ring-shapedtransport arrangement 112″.

REFERENCE LIST

 1 transport chamber  3 transport chamber pump arrangement  5 transportarrangement  7 workpiece support  9 workpiece  11 opening  13 vacuumtreatment chamber  13_(T) workpiece treatment compartment  13_(P)pumping compartment  15 support  17 sealing arrangement  18 pumping port 19 pumping arrangement  20 drive  20′ drive for seal  21 tubular bellow 22 drive for the transport arrangement 5  25 sealing ring or frame  27shoulder surface  31 through-opening  33 shoulder  35 workpiece carrierplate  37 lifting rod  39 lead through  41 lifting plate  61 transportchamber  65 transport arrangement  66 workpiece support area  71 opposedpump  73 vacuum treatment chamber  75_(T) treatment compartment  75_(P)pumping compartment  77 through opening in 65  79 sealing ring  81support member  83 tubular bellow  85 ring shoulder surface  87 secondsealing ring  89 lifting rod  91 vacuum-tight lead through  93 drive  95flange  97 spring arrangement  99 lifting plate 101 pumping port 75_(P)′ pumping area 103 lifting plate 107 workpiece 109 Pin 111 Drive115 Heating and/or cooling facility 117 Temperature sensing device 119Comparator unit

The invention claimed is:
 1. A vacuum treatment apparatus comprising: avacuum treatment chamber (13, 73) to perform a desired workpiecetreatment of a workpiece and with a rigid wall; a vacuum transportchamber (1, 61); a handling opening common to said vacuum treatmentchamber and to said vacuum transport chamber; a workpiece transport (5,65) for handling a workpiece from said vacuum transport chamber throughsaid handling opening and into said vacuum treatment chamber, saidtransport being drivingly movable along a movement path (S) extendingfrom said vacuum transport chamber through said handling opening and insaid vacuum treatment chamber, said vacuum treatment chamber (13, 73)comprising a workpiece treatment compartment (13T, 75T) for a workpieceto which a surface of a workpiece to be treated is exposed fortreatment, said vacuum treatment compartment being located on one sideof said movement path (S) in said vacuum treatment chamber and beingequipped to perform the workpiece treatment and a pumping compartment(13P, 75P) opposite said workpiece treatment compartment (13T, 75T) withrespect to said movement path (S) in said vacuum treatment chamber; apumping port arrangement for said workpiece treatment compartment, saidpumping port arrangement consisting of at least one pumping port in saidpumping compartment; a controllable seal (17, 17 a, 109, 79, 87, 83, 85)within said treatment chamber and controllably sealing off or freeing afirst gas flow communication between said vacuum transport chamber (1,61) and said pumping port (18, 101) through said handling opening andbeing constructed so that a pressure difference existing between thevacuum treatment chamber at a higher pressure and the transport chamberat lower pressure relative to the pressure in the treatment chamberprovides for an increased sealing force upon sealing off said opening.2. The apparatus of claim 1, wherein said controllable seal is conceivedto increase sealing force as a pressure in said treatment compartmentand in an area of said pumping compartment in flow communication withsaid pumping port increases.
 3. The apparatus of claim 1, wherein saidcontrollable seal is conceived to seal off said opening as saidworkpiece transport is in a position at which said workpiece transportis within said vacuum treatment chamber.
 4. The apparatus of claim 1,wherein said controllable seal comprises a drivingly extendable andretractable tubular bellow, one end thereof being sealingly mounted insaid pumping compartment, an other end thereof being controllablymovable about said opening to seal off said opening, said pumping portbeing located in an area of said pumping compartment which is in flowcommunication with an inside of said bellow.
 5. The apparatus of claim4, said transport chamber extending across said vacuum treatment chamberand communicating with a second handling opening opposite said onehandling opening, said other end of said bellow being sealingly movableabout said second handling opening as well.
 6. The apparatus of claim 5,said workpiece transport being movable along said movement path throughsaid vacuum treatment chamber and through said first and a secondhandling opening.
 7. The apparatus of claim 4, comprising a workpiecesupport being adapted to support a workpiece on said workpiece transportand in said treatment chamber, said workpiece transport comprising athrough opening, said workpiece support being held in said throughopening and liftable in a direction towards said treatment compartment,said other end of said tubular bellow being drivingly movable in sealingcontact with said workpiece support so as to lift it into sealingcontact with an annular area along the wall of said treatment chamber.8. The apparatus of claim 7 comprising a lift arrangement controllablyliftable from said pumping compartment towards said treatmentcompartment and located inside said tubular bellow and comprising anactuator to liftably cooperate with said other end of said tubularbellow so as to lift it into said sealing contact with said workpiecesupport.
 9. The apparatus of claim 8, said workpiece support comprisinga frame comprising holding members adapted for a holding workpiecewithin an open area of said frame, said holding members being adapted toallow lifting of a workpiece from said frame in the direction towardssaid treatment compartment, said actuator cooperating via a springarrangement with said other end of said tubular bellow, said liftarrangement comprising a plate located at the end of said liftarrangement towards said treatment compartment.
 10. The apparatus ofclaim 7, said other end of said tubular bellow being sealingly mountedto a ringplate, said actuator comprising a support plate with throughopenings.
 11. The apparatus of claim 7, said workpiece transport beingmovable along said transport path through said vacuum treatment chamberand through first and second of said handling openings and comprising amultitude of spaced apart of said workpiece support.
 12. The apparatusof claim 11, said transport being movable along a linear or circularmoving path.
 13. The apparatus of claim 12, said workpiece transportbeing movable along the circular moving path, said treatment compartmentand said pumping compartment being arranged opposite each other indirection of an axis of said circular moving path.
 14. The apparatus ofclaim 1, further comprising, a pumping arrangement connected to saidpumping port and being operationally connectable to a pumping port ofsaid vacuum transport chamber.
 15. The apparatus of claim 1 comprising acontrollably drivable lifting arrangement in said treatment chamberadapted for lifting a workpiece.
 16. The apparatus of claim 15comprising a temperature sensor adapted to sense a temperature of aworkpiece, said temperature sensor and said controllably drivablelifting arrangement being operatively connected in a negative feedbackloop for the temperature of a workpiece.
 17. The apparatus of claim 1comprising a workpiece support being adapted to support a workpiece onsaid workpiece transport and in said treatment chamber, said workpiecesupport being applicable to said workpiece transport.